An Integrated Microfluidic Real-Time PCR System for Pathogen Detection

The development of microfluidics-based PCR for rapid genetic analysis particularly pathogen detection is an emerging research field. Recent advancement of microfluidics critically enabled the development of various on-chip PCR systems to realize its apparent advantages in reaction throughput and efficiency, and low reagent consumption. However, further realizing the potential of microfluidics-based PCR for practical biomedical diagnosis requires system integration to effectively connect individual function modules as oppose to the large microscopy-based methods and other offline systems that is often limited in its detection efficiency and accuracy. Here we present a fully-integrated microfluidic real-time PCR system with thermal cycler and online fluorescence detection module. The PCR microfluidic chip was fabricated in PDMS (Polydimethylsiloxane) for rapid prototyping. The thermal cycler allows rapid temperature cycling with high accuracy. The fluorescence detection module permits continuous monitoring of the PCR reaction in the microfluidic chip over thermal cycles, and real-time image/signal data processing and analysis through the build-in computer. Using this developed system, we successfully demonstrated real-time PCR detection of E.coli O157:H7 with 20 L of PCR reaction mixture. Further development will lead to a more compact and portable microfluidic real-time PCR system that offers a useful tool for various biomedical research and clinical applications.